Ask HN: How to add money to my own bootstrapped startup?

Context: Delaware C corp, US resident

Hi there, I recently incorporated and I want to separate my personal finances from the company. To do that, I want to loan my own money to the company (I know buying stocks is also an option but I am avoiding it as it deemed more complicated to me at this point; feel free to object). How much interest should I charge the company? Is there any blog post or any resource that you can share? I have already done some research and I am aware of the Applicable Federal Rates. I just don't know which number to use and I also hope to find some boilerplate documents.

(of course I am not seeking legal advice and all readers including me should take all the responsibilities of all the actions they take)